// 创建动画
.ReactCSSTransitionGroup(@name, @enter, @enterActive, @leave: @enter, @leaveActive: @enterActive) {
  .@{name}-enter {
    @enter();
  }
  .@{name}-enter.@{name}-enter-active {
    @enterActive();
  }
  .@{name}-leave {
    @leave();
  }
  .@{name}-leave.@{name}-leave-active {
    @leaveActive();
  }
}

/*
示例
.ReactCSSTransitionGroup(
  动画标识名,
  {进入动画 - 开始},
  {进入动画 - 结束},
  {离开动画 - 开始},
  {离开动画 - 结束}
);
 */
